Coordinated multipoint (CoMP) radio resource management (RRM) measurement

ABSTRACT

A method performed by a user equipment (UE) is described. A measurement configuration is received from an evolved NodeB (eNB). The measurement configuration comprises a measurement object in a carrier frequency and the measurement object comprises a set of channel state information reference signal (CSI-RS) configurations. A measurement is performed based on a cell-specific reference signal (CRS). A measurement is performed based on a channel state information reference signal (CSI-RS) based on the measurement configuration. A measurement report is generated in a radio resource control (RRC) layer. The measurement report is sent to the eNB.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/433,218 entitled “COORDINATED MULTIPOINT (COMP) RADIO RESOURCEMANAGEMENT (RRM) MEASUREMENT,” filed Mar. 28, 2012, which isincorporated herein by reference.

TECHNICAL FIELD

The present invention relates generally to wireless communications andwireless communications-related technology. More specifically, thepresent invention relates to systems and methods for coordinatedmultipoint (CoMP) radio resource management (RRM) measurement.

BACKGROUND

Wireless communication devices have become smaller and more powerful inorder to meet consumer needs and to improve portability and convenience.Consumers have become dependent upon wireless communication devices andhave come to expect reliable service, expanded areas of coverage andincreased functionality. A wireless communication system may providecommunication for a number of cells, each of which may be serviced by abase station. A base station may be a fixed station that communicateswith mobile stations.

Various signal processing techniques may be used in wirelesscommunication systems to improve efficiency and quality of wirelesscommunication. In Rel-10, multiple component carriers (CCs) wereintroduced. The use of coordinated multipoint (CoMP) transmission isconsidered a major enhancement to Long Term Evolution (LTE) Release 11.Benefits may be realized by improvements to the use of coordinatedmultipoint (CoMP) transmission. Benefits may also be realized byimproved methods for reporting measurement results by a wirelesscommunication device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating a wireless communication systemusing uplink control information (UCI) multiplexing;

FIG. 2 is a block diagram illustrating a wireless communication systemthat may utilize coordinated multipoint (CoMP) transmission;

FIG. 3 is a block diagram illustrating the layers used by a userequipment (UE);

FIG. 4 is a block diagram illustrating a homogenous network withintra-site coordinated multipoint (CoMP);

FIG. 5 is a block diagram illustrating a homogenous network with high Txpower remote radio heads (RRHs);

FIG. 6 is a block diagram illustrating a network with low Tx powerremote radio heads (RRHs) within the macrocell coverage;

FIG. 7 is a block diagram illustrating a generalized coordinatedmultipoint (CoMP) architecture;

FIG. 8 is a block diagram illustrating the structure of a measurementconfiguration variable;

FIG. 9 is a block diagram illustrating the structure of a measurementreport list;

FIG. 10 is a block diagram illustrating an RRC ConnectionReconfiguration message structure;

FIG. 11 is a flow diagram of a method for coordinated multipoint (CoMP)radio resource management (RRM) measurement;

FIG. 12 is a flow diagram of a method for coordinating a coordinatedmultipoint (CoMP) radio resource management (RRM) measurement;

FIG. 13 illustrates the transmission of a measurement configuration froman eNB to a user equipment (UE);

FIG. 14 is a block diagram illustrating an independent configuration forthe channel state information reference signal (CSI-RS);

FIG. 15 is a block diagram illustrating an independent configuration forchannel state information reference signal (CSI-RS);

FIG. 16 is a block diagram illustrating a configuration for channelstate information reference signal (CSI-RS) in the physicalconfiguration;

FIG. 17 is a block diagram illustrating a measurement object andindependent configuration for channel state information reference signal(CSI-RS);

FIG. 18 is a block diagram illustrating how a report configuration mayindicate that a measurement ID in a measurement configuration iscell-specific reference signal (CRS) based or channel state informationreference signal (CSI-RS) based;

FIG. 19 is a block diagram illustrating how a measurement object 1979a-c may indicate that a measurement ID in a measurement configuration isfor cell-specific reference signal (CRS) or channel state informationreference signal (CSI-RS);

FIG. 20 illustrates various components that may be utilized in a userequipment (UE);

FIG. 21 illustrates various components that may be utilized in an eNB.

FIG. 22 is a block diagram illustrating one configuration of a UE inwhich systems and methods for coordinated multipoint (CoMP) radioresource management (RRM) measurement may be implemented; and

FIG. 23 is a block diagram illustrating one configuration of an eNB inwhich systems and methods for coordinated multipoint (CoMP) radioresource management (RRM) measurement may be implemented.

DETAILED DESCRIPTION

A method for measurement reporting is described. A measurementconfiguration is received from an evolved Node B (eNB). The measurementconfiguration includes a single measurement object in a carrierfrequency. A measurement report for a channel state informationreference signal (CSI-RS) is generated based on the measurementconfiguration. The measurement report is sent to the eNB.

The method may be performed by a user equipment (UE). The measurementobject may include a set of channel state information reference signal(CSI-RS) configurations for reference signal received power (RSRP)measurement. The measurement object may also include a set of channelstate information reference signal (CSI-RS) configurations for referencesignal received quality (RSRQ) measurement. A radio resourceconfiguration of the measurement object may include a set of channelstate information reference signal (CSI-RS) configurations. The set ofCSI-RS configurations may be used for channel quality measurement in aphysical layer. The set of CSI-RS configurations may also be used forchannel quality reporting in a physical layer.

The measurement object may include a report configuration. The reportconfiguration may indicate that the measurement object corresponds toone of a cell-specific reference signal (CRS) and a channel stateinformation reference signal (CSI-RS). The measurement object mayinclude a measurement object. The measurement object may indicate thatthe measurement object corresponds to one of a cell-specific referencesignal (CRS) and a channel state information reference signal (CSI-RS).

Each measurement configuration may include multiple measurement IDs,multiple measurement objects and multiple report configurations. Eachmeasurement ID may be linked to a measurement object and a reportconfiguration. A measurement object configuration of the measurementconfiguration may include one or more sets of channel state informationreference signal (CSI-RS) configurations.

The measurement configuration may include a measurement object thatincludes an information element configured to perform at least one ofadding to the sets of CSI-RS configurations, modifying the sets ofCSI-RS configurations and removing from the sets of CSI-RSconfigurations. Each measurement object may correspond to a specificcarrier frequency. Each measurement object may also correspond to one ofcell-specific reference signal (CRS) based RRM measurement or CSI-RSbased RRM measurement.

A physical configuration of the measurement configuration may includeone or more sets of channel state information reference signal (CSI-RS)configurations. The physical configuration may include an informationelement configured to perform at least one of adding to the sets ofCSI-RS configurations, modifying the sets of CSI-RS configurations andremoving from the sets of CSI-RS configurations.

A method for measurement reporting is also described. Measurementsettings for a channel state information reference signal (CSI-RS) aredetermined for a user equipment (UE). A measurement configuration forthe UE is generated. The measurement configuration includes a singlemeasurement object in a carrier frequency. The measurement configurationis sent to the UE.

The method may be performed by an eNB.

A user equipment (UE) configured for measurement reporting is described.The user equipment (UE) includes a processor, memory in electroniccommunication with the processor and instructions stored in the memory.The instructions are executable to receive a measurement configurationfrom an evolved Node B (eNB). The measurement configuration includes asingle measurement object in a carrier frequency. The instructions arealso executable to generate a measurement report for a channel stateinformation reference signal (CSI-RS) based on the measurementconfiguration. The instructions are further executable to send themeasurement report to the eNB.

An evolved NodeB (eNB) configured for measurement reporting is alsodescribed. The eNB includes a processor, memory in electroniccommunication with the processor and instructions stored in the memory.The instructions are executable to determine measurement settings for achannel state information reference signal (CSI-RS) for a user equipment(UE). The instructions are also executable to generate a measurementconfiguration for the UE. The measurement configuration includes asingle measurement object in a carrier frequency. The instructions arefurther executable to send the measurement configuration to the UE.

The 3rd Generation Partnership Project, also referred to as “3GPP,” is acollaboration agreement that aims to define globally applicabletechnical specifications and technical reports for third and fourthgeneration wireless communication systems. The 3GPP may definespecifications for the next generation mobile networks, systems anddevices.

3GPP Long Term Evolution (LTE) is the name given to a project to improvethe Universal Mobile Telecommunications System (UMTS) mobile phone ordevice standard to cope with future requirements. In one aspect, UMTShas been modified to provide support and specification for the EvolvedUniversal Terrestrial Radio Access (E-UTRA) and Evolved UniversalTerrestrial Radio Access Network (E-UTRAN).

At least some aspects of the systems and methods disclosed herein may bedescribed in relation to the 3GPP LTE and LTE-Advanced standards (e.g.,Release-8, Release-9, Release-10 and Release-11). However, the scope ofthe present disclosure should not be limited in this regard. At leastsome aspects of the systems and methods disclosed herein may be utilizedin other types of wireless communication systems.

In LTE Release-11, the use of coordinated multipoint (CoMP) transmissionis a major enhancement. In coordinated multipoint (CoMP) transmission, auser equipment (UE) may be able to receive downlink signals frommultiple geographically separated antennas (referred to herein aspoints). Points may be located on the same base station or on differentbase stations. Points may be connected to a base station but be in adifferent physical location than the base station. Furthermore, uplinktransmissions by the user equipment (UE) may be received by the multiplepoints. Sectors of the same site may correspond to different points.

Each point may be controlled by an eNB. There may be one or multipleeNBs. One of the eNBs may be referred to as the serving eNB. The servingeNB may perform most of the processing, such as baseband processing andscheduling. Because some of the antennas might be collocated at an eNB,the eNB may also be a point. The serving eNB may control one or multiplecells. One cell may be designated as the serving cell. The designationof a cell as the serving cell may dynamically change over time. One ormore points may be used for transmission or reception in each cell.

An antenna port may be defined such that the channel over which a symbolon the antenna port is conveyed can be inferred from the channel overwhich another symbol on the same antenna port is conveyed. There may beone resource grid (time-frequency) per antenna port. The antenna portcan realize multiple layers for a multiple-input and multiple-output(MIMO) system. The points may be transparent to the user equipment (UE).To a user equipment (UE), antenna ports are distinguishable. An antennaport may be realized by an antenna or set of antennas in one point or aset of antennas in different points. However, points are distinguishablefrom the perspective of an eNB. Therefore, in a transmission from apoint to the user equipment (UE), from the perspective of the eNB, theeNB knows which point(s) are used for an antenna port participating inthe transmission.

By coordinating the downlink transmissions from each point to the userequipment (UE), the downlink performance can be significantly increased.Likewise, by coordinating the uplink transmissions from the userequipment (UE), the multiple points may take advantage of the multiplereceptions to significantly improve the uplink performance. Incoordinated multipoint (CoMP) transmissions, the channel stateinformation (CSI) of each coordinated point may be reported separatelyor jointly with the same format as Release-10 or new formats.

The use of coordinated multipoint (CoMP) transmission may increaseuplink and downlink data transmission rates while ensuring consistentservice quality and throughput on LTE wireless broadband networks and 3Gnetworks. Coordinated multipoint (CoMP) transmission may be used on boththe uplink and the downlink.

Two major coordinated multipoint (CoMP) transmission methods are underconsideration: coordinated scheduling/coordinated beamforming (CS/CB)and joint processing (JP). In coordinated scheduling/coordinatedbeamforming (CS/CB), the scheduling of the transmission (includingbeamforming functionality) may be dynamically coordinated between thepoints (i.e., the points in a serving coordinated multipoint (CoMP)cooperating set) to control/reduce the interference between differentcoordinated multipoint (CoMP) and non-coordinated multipoint (CoMP)transmissions. In joint processing (JP) (also referred to as jointtransmission (JT)), the data may be transmitted by only one transmissionpoint to the user equipment (UE). Dynamic point selection (DPS),including dynamic point blanking, may also be used.

The term “simultaneous” may be used herein to denote a situation wheretwo or more events occur in overlapping time frames. In other words, two“simultaneous” events may overlap in time to some extent, but are notnecessarily of the same duration. Furthermore, simultaneous events mayor may not begin or end at the same time.

FIG. 1 is a block diagram illustrating a wireless communication system100 using uplink control information (UCI) multiplexing. An eNB 102 maybe in wireless communication with one or more user equipments (UEs) 104.An eNB 102 may be referred to as an access point, a Node B, an evolvedNode B, a base station or some other terminology. Likewise, a userequipment (UE) 104 may be referred to as a mobile station, a subscriberstation, an access terminal, a remote station, a user terminal, aterminal, a handset, a subscriber unit, a wireless communication device,or some other terminology.

Communication between a user equipment (UE) 104 and an eNB 102 may beaccomplished using transmissions over a wireless link, including anuplink and a downlink. The uplink refers to communications sent from auser equipment (UE) 104 to an eNB 102. The downlink refers tocommunications sent from an eNB 102 to a user equipment (UE) 104. Thecommunication link may be established using a single-input andsingle-output (SISO), multiple-input and single-output (MISO),single-input and multiple-output (SIMO) or a multiple-input andmultiple-output (MIMO) system. A MIMO system may include both atransmitter and a receiver equipped with multiple transmit and receiveantennas. Thus, an eNB 102 may have multiple antennas 110 a-n and a userequipment (UE) 104 may have multiple antennas 112 a-n. In this way, theeNB 102 and the user equipment (UE) 104 may each operate as either atransmitter or a receiver in a MIMO system. One benefit of a MIMO systemis improved performance if the additional dimensionalities created bythe multiple transmit and receive antennas are utilized.

The user equipment (UE) 104 communicates with an eNB 102 using one ormore antenna ports, which may be realized by one or more physicalantennas 112 a-n. The user equipment (UE) 104 may include a transceiver132, a decoder 124, an encoder 128 and an operations module 116. Thetransceiver 132 may include a receiver 133 and a transmitter 135. Thereceiver 133 may receive signals from the eNB 102 using one or moreantennas 112 a-n. For example, the receiver 133 may receive anddemodulate received signals using a demodulator 134. The transmitter 135may transmit signals to the eNB 102 using one or more antenna ports,which may be realized by one or more physical antennas 112 a-n. Forexample, the transmitter 135 may modulate signals using a modulator 136and transmit the modulated signals.

The receiver 133 may provide a demodulated signal to the decoder 124.The user equipment (UE) 104 may use the decoder 124 to decode signalsand make downlink decoding results 126. The downlink decoding results126 may indicate whether data was received correctly. For example, thedownlink decoding results 126 may indicate whether a packet wascorrectly or erroneously received (i.e., positive acknowledgement,negative acknowledgement or discontinuous transmission (no signal)).

The operations module 116 may be a software and/or hardware module usedto control user equipment (UE) 104 communications. For example, theoperations module 116 may determine when the user equipment (UE) 104requires resources to communicate with an eNB 102.

In 3^(rd) Generation Partnership Project (3GPP) Long Term Evolution(LTE)—Advanced, additional control feedback will have to be sent oncontrol channels to accommodate MIMO and carrier aggregation. Carrieraggregation refers to transmitting data on multiple component carriers(CCs) (or cells) that are contiguously or separately located. Both thehybrid automatic repeat and request (ARQ) acknowledgement (HARQ-ACK)with positive-acknowledge and negative-acknowledge (ACK/NACK) bits andother control information may be transmitted using the physical uplinkcontrol channel (PUCCH) or the physical uplink shared channel (PUSCH).In carrier aggregation (CA), only one uplink component carrier (CC) (orcell) (i.e., PCC or PCell) may be utilized for transmission using thephysical uplink control channel (PUCCH). A component carrier (CC) is acarrier frequency to which cells belong.

The user equipment (UE) 104 may transmit uplink control information(UCI) 120 a to an eNB 102 on the uplink. The uplink control information(UCI) 120 a may include a channel state information (CSI), a schedulingrequest (SR) and a hybrid automatic repeat request acknowledgement(HARQ-ACK). HARQ-ACK means ACK (positive-acknowledgement) and/or NACK(negative-acknowledgement) and/or DTX (discontinuous transmission)responses for HARQ operation, also known as ACK/NACK. If a transmissionis successful, the HARQ-ACK may have a logical value of 1 and if thetransmission is unsuccessful, the HARQ-ACK may have a logical value of0.

The channel state information (CSI) includes a channel quality indicator(CQI), a precoding matrix indicator (PMI), a precoding type indicator(PTI) and/or rank indication (RI).

The uplink control information (UCI) 120 a may be generated by theuplink control information (UCI) reporting module 118 and transferred toan encoder 128. The operations module 116 may also generate radioresource management (RRM) measurement reports 122 a. The radio resourcemanagement (RRM) measurement report 122 a may be provided to the encoder128. The encoder 128 may then provide the uplink control information(UCI) 120 for transmission and the radio resource management (RRM)report 122 a to the transmitter 135. In one configuration, the radioresource management (RRM) report 122 a may be processed in the radioresource control (RRC) layer and the uplink control information (UCI)120 a may be processed in the physical (PHY) layer.

The time and frequency resources may be quantized to create a grid knownas the time-frequency grid. In the time domain, 10 milliseconds (ms) isreferred to as one radio frame. One radio frame may include 10subframes, each with a duration of 1 ms, which is the duration oftransmission in the uplink and/or downlink. Every subframe may bedivided into two slots, each with a duration of 0.5 ms. Each slot may bedivided into 7 symbols. The frequency domain may be divided into bandswith a 15 kilohertz (kHz) width, referred to as a subcarrier. Oneresource element has a duration of one symbol in the time domain and thebandwidth of one subcarrier in the frequency domain.

The minimum amount of resource that can be allocated for thetransmission of information in the uplink or downlink in any givensubframe is two resource blocks (RBs), with one RB at each slot. One RBhas a duration of 0.5 ms (7 symbols or one slot) in the time domain anda bandwidth of 12 subcarriers (180 kHz) in the frequency domain. At anygiven subframe, a maximum of two RBs (one RB at each slot) can be usedby a given user equipment (UE) 104 for the transmission of uplinkcontrol information (UCI) in the physical uplink control channel(PUCCH).

In LTE Release-8, only one uplink component carrier (CC) 106 or cell 107and one downlink component carrier (CC) 108 or cell 107 can be used fortransmission to and reception from each user equipment (UE) 104.

In 3GPP Long Term Evolution (LTE) Release-10 (LTE-A or Advanced EUTRAN),carrier aggregation was introduced. Carrier aggregation may also bereferred to as cell aggregation. Carrier aggregation is supported inboth the uplink and the downlink with up to five component carriers(CCs) 106, 108. Each component carrier (CC) 106, 108 or cell 107 mayhave a transmission bandwidth of up to 110 resource blocks (i.e., up to20 megahertz (MHz)). In carrier aggregation, two or more componentcarriers (CCs) 106, 108 are aggregated to support wider transmissionbandwidths up to one hundred megahertz (MHz). A user equipment (UE) 104may simultaneously receive and/or transmit on one or multiple componentcarriers (CCs) 106, 108, depending on the capabilities of the userequipment (UE) 104.

A user equipment (UE) 104 may communicate with an eNB 102 using multiplecomponent carriers (CCs) 108 at the same time. For example, a userequipment (UE) 104 may communicate with an eNB 102 using a primary cell(PCell) 107 a while simultaneously communicating with the eNB 102 usingsecondary cell(s) (SCell) 107 b. Similarly, an eNB 102 may communicatewith a user equipment (UE) 104 using multiple component carriers (CCs)108 at the same time. For example, an eNB 102 may communicate with auser equipment (UE) 104 using a primary cell (PCell) 107 a whilesimultaneously communicating with the user equipment (UE) 104 usingsecondary cell(s) (SCell) 107 b.

An eNB 102 may include a transceiver 137 that includes a receiver 138and a transmitter 140. An eNB 102 may additionally include a decoder142, an encoder 144 and an operations module 146. An eNB 102 may receiveuplink control information (UCI) 120 b and radio resource management(RRM) measurement reports 122 b using its one or more antenna ports,which may be realized by one or more physical antennas 110 a-n, and itsreceiver 138. The receiver 138 may use the demodulator 139 to demodulatethe uplink control information (UCI) 120 b and the radio resourcemanagement (RRM) measurement reports 122 b.

The decoder 142 may include an uplink control information (UCI)receiving module 143. An eNB 102 may use the uplink control information(UCI) receiving module 143 to decode and interpret the uplink controlinformation (UCI) 120 b received by the eNB 102. The eNB 102 may use thedecoded uplink control information (UCI) 120 b to perform certainoperations, such as retransmit one or more packets based on scheduledcommunication resources for the user equipment (UE) 104. The decoder 142may also decode the radio resource management (RRM) measurement report122 b. The radio resource management (RRM) measurement report 122 b maybe defined for the purpose of inter-cell mobility management in theradio resource control (RRC) layer. The radio resource management (RRM)measurement report 122 b may be used to efficiently select coordinatedmultipoint (CoMP) transmission points and/or to select efficient channelstate information (CSI) measurement sets in the physical layer.

The operations module 146 may include a retransmission module 147 and ascheduling module 148. The retransmission module 147 may determine whichpackets to retransmit (if any) based on the uplink control information(UCI) 120 b. The scheduling module 148 may be used by the eNB 102 toschedule communication resources (e.g., bandwidth, time slots, frequencychannels, spatial channels, etc.). The scheduling module 148 may use theuplink control information (UCI) 120 b to determine whether (and when)to schedule communication resources for the user equipment (UE) 104.

The operations module 146 may provide data 145 to the encoder 144. Forexample, the data 145 may include packets for retransmission and/or ascheduling grant for the user equipment (UE) 104. The encoder 144 mayencode the data 145, which may then be provided to the transmitter 140.The transmitter 140 may modulate the encoded data using the modulator141. The transmitter 140 may transmit the modulated data to the userequipment (UE) 104 using one or more antenna ports, which may berealized by the one or more physical antennas 110 a-n.

When carrier aggregation is configured, a user equipment (UE) 104 mayhave only one radio resource control (RRC) connection with the network.At the radio resource control (RRC) connectionestablishment/re-establishment/handover, one serving cell 107 (i.e., theprimary cell (PCell) 107 a) provides the non-access stratum (NAS)mobility information (e.g., Tracking Area Identity (TAI)) and thesecurity input.

In the downlink, the component carrier (CC) 108 corresponding to theprimary cell (PCell) 107 a is the downlink primary component carrier (DLPCC) 108 a. In the uplink, the component carrier (CC) 106 correspondingto the primary cell (PCell) 107 a is the uplink primary componentcarrier (UL PCC) 106 a. Depending on the capabilities of the userequipment (UE) 104, one or more secondary component carriers (SCC) 106b, 108 b or secondary cells (SCell) 107 b may be configured to form aset of serving cells with the primary cell (PCell) 107 a. In thedownlink, the component carrier (CC) 108 corresponding to the secondarycell (SCell) 107 b is the downlink secondary component carrier (DL SCC)108 b. In the uplink, the component carrier (CC) 106 corresponding tothe secondary cell (SCell) 107 b is the uplink secondary componentcarrier (UL SCC) 106 b. The number of downlink component carriers (CCs)108 may be different from the number of uplink component carriers (CCs)106 because multiple cells may share one uplink component carrier (CC)106.

If carrier aggregation is configured, a user equipment (UE) 104 may havemultiple serving cells: a primary cell (PCell) 107 a and one or moresecondary cells (SCell) 107 b. From a network perspective, a servingcell 107 may be used as the primary cell (PCell) 107 a by one userequipment (UE) 104 and used as a secondary cell (SCell) 107 b by anotheruser equipment (UE) 104. If carrier aggregation is not configured, aprimary cell (PCell) 107 a operates a single serving cell. There may beone or more secondary cells (SCell) 107 b in addition to the primarycell (PCell) 107 a if carrier aggregation is configured. One benefit ofusing carrier aggregation is that additional downlink and/or uplink datamay be transmitted. As a result of the additional downlink data,additional uplink control information (UCI) 120 may be needed.

A number of spatial channels may be available on each serving cell 107by using multiple antenna ports at a transmitter and a receiver.Therefore, multiple codewords (up to two codewords) may be transmittedsimultaneously.

A channel state information (CSI) report may be generated for eachcomponent carrier (CC) 106, 108 or cell 107. In Rel-10, channel stateinformation (CSI) reporting for up to five downlink component carriers(CCs) 108 may be supported. A channel state information (CSI) report maybe used to inform the eNB 102 to adjust the transmission rate(modulation scheme and coding rate) dynamically based on the existingchannel conditions at the user equipment (UE) 104. For example, if achannel state information (CSI) report indicates a good channel qualityat the user equipment (UE) 104, the eNB 102 may select a higher ordermodulation and coding rate, thereby achieving a higher transmission ratefor the downlink transmission of data on the physical downlink sharedchannel (PDSCH). If a channel state information (CSI) report indicates apoor channel quality at the user equipment (UE) 104, the eNB 102 mayselect a lower order modulation and coding rate, thereby achievinghigher reliability for the transmission.

The channel state information (CSI) may include a channel qualityindicator (COI), a precoding matrix indicator (PMI), a precoding typeindicator (PTI) and/or rank indication (RI). A channel state information(CSI) report may be referred to as a rank indication (RI) report if thechannel state information (CSI) report only includes rank indication(RI). A channel state information (CSI) report may be referred to as achannel quality indicator (CQI) report if the channel state information(CSI) report only includes a channel quality indicator (CQI). A channelstate information (CSI) report may be referred to as a precoding matrixindicator (PMI) report if the channel state information (CSI) reportonly includes a precoding matrix indicator (PMI).

FIG. 2 is a block diagram illustrating a wireless communication system200 that may utilize coordinated multipoint (CoMP) transmission. Thewireless communication system 200 may include a first point 202 a incommunication with a user equipment (UE) 204 and a second point 202 b incommunication with the user equipment (UE) 204. Additional points (notshown) may also be in communication with the user equipment (UE) 204.

All points 202 communicating with a user equipment (UE) 204 may bereferred to as transmission points 202. For simplicity, reference isalso made herein to only a single transmission point 202, even thoughthere may be multiple transmission points 202. There may be acommunication link 205 between each of the points 202.

As used herein, a cooperating set refers to a set of geographicallyseparated points 202 directly and/or indirectly participating in datatransmission to a user equipment (UE) 204 in a time-frequency resource.The cooperating set may or may not be transparent to the user equipment(UE) 204. Thus, the set of transmission points 202 is a subset of thecooperating set.

A point 202 may be controlled by a base station. Communication between auser equipment (UE) 204 and a point 202 may be accomplished usingtransmissions over a wireless link, including an uplink 211 a-b and adownlink 209 a-b. The uplink 211 refers to communications sent from auser equipment (UE) 204 to one or more points 202 (referred to asreception points 202). The downlink 209 refers to communications sentfrom one or more points 202 (referred to as transmission points 202) toa user equipment (UE) 204. The set of reception points 202 may includenone, some or all of the points 202 in the set of transmission points202. Likewise, the set of transmission points 202 may include none, someor all of the points 202 in the set of reception points 202. A point 202and a user equipment (UE) 204 may each operate as either a transmitteror a receiver in a MIMO system.

There has recently been a lot of interest in coordinated multipoint(CoMP) transmission schemes where multiple transmission points 202cooperate. There has also been discussion on how to improve the feedbackscheme for both coordinated multipoint (CoMP) transmission and multiuserMIMO schemes. The point 202 may make a decision concerning the use ofcoordinated multipoint (CoMP) transmission and the coordinatedmultipoint (CoMP) transmission method used based on feedback from theuser equipment (UE) 204. Depending on the channel conditions observed bya user equipment (UE) 204, coordinated multipoint (CoMP) transmissionoperation and the coordinated multipoint (CoMP) transmission method ofeach cell may be configured dynamically and independently.

The user equipment (UE) 204 may include a measurement module 249. Themeasurement module 249 may include a measurement configuration 250. Themeasurement configuration 250 may define the settings for the userequipment (UE) 204 to generate and transmit a measurement report 252 tothe network. The measurement report 252 may be generated by a feedbackmodule 251 on the user equipment (UE) 204. The user equipment (UE) 204may then transmit the measurement report to the E-UTRAN (e.g., theserving eNB 102, a neighbor eNB 102 and/or a network). Morespecifically, in Rel-11, coordinated multipoint (CoMP) radio resourcemanagement (RRM) measurement is introduced to achieve setting efficientcoordinated multipoint (CoMP) transmission points and/or to choose anefficient channel state information (CSI) measurement set in thephysical layer. In Rel-10, radio resource management (RRM) measurementcan only support cell-specific reference signal (CRS) based referencesignal received power (RSRP)/reference signal received quality (RSRQ)measurement.

For coordinated multipoint (CoMP) radio resource management (RRM)measurement, one or more channel state information reference signals(CSI-RSs) are needed to measure the channels of transmission points. Theuser equipment (UE) 204 does not need to know the linking betweentransmission points 202 and channel state information reference signals(CSI-RSs). From measurement reports of CSI-RSs, the E-UTRAN can know theconditions of transmission points 202, because the E-UTRAN knows thelinking between transmission points 202 and channel state informationreference signals (CSI-RSs). Coordinated multipoint (CoMP) radioresource management (RRM) measurement may generate a radio resourcemanagement (RRM) measurement report 252 that is then transmitted by theuser equipment (UE) 204 to the network. Channel state informationreference signal (CSI-RS) based radio resource management (RRM)measurement may be used for both coordinated multipoint (CoMP) radioresource management (RRM) measurement and other purposes (e.g.,mobility, load sharing, radio resource management). Therefore,configurations for coordinated multipoint (CoMP) radio resourcemanagement (RRM) measurement may be considered as configurations forchannel state information reference signal (CSI-RS) based radio resourcemanagement (RRM) measurement.

In Rel-10, radio resource management (RRM) measurement is definedprimarily for inter-cell mobility management in the radio resourcecontrol (RRC) layer. The user equipment (UE) 204 may receive ameasurement configuration 250 from the E-UTRAN (e.g., the serving eNB102, a neighbor eNB 102 and/or a network). The E-UTRAN may provide themeasurement configuration applicable for a user equipment (UE) 204 inRRC_CONNECTED by means of dedicated signaling (i.e., using theRRCConnectionReconfiguration message).

The measurement configuration 250 may instruct the user equipment (UE)204 to obtain intra-frequency measurements (i.e., measurements at thedownlink carrier frequencies of the serving cells 107), inter-frequencymeasurements (i.e., measurements at frequencies that differ from any ofthe downlink carrier frequencies of the serving cells 107) and inter-RATmeasurements.

A measurement configuration 250 may include measurement objects,reporting configurations, measurement identities, quantityconfigurations and measurement gaps. Measurement objects refer to theobjects on which the user equipment (UE) 204 performs measurements. Forintra-frequency and inter-frequency measurements, a measurement objectmay be a single E-UTRA carrier frequency. Associated with this carrierfrequency, the E-UTRAN may configure a list of cell specific offsets anda list of blacklisted cells. Blacklisted calls are those cells that arenot considered in event evaluation or measurement reporting.

Reporting configurations may include reporting criterion that triggersthe user equipment (UE) 204 to send a measurement report 252. Thereporting criterion may be either periodical or a single eventdescription. Reporting configurations may also include the reportingformat. The reporting format may define the quantities that the userequipment (UE) 204 includes in a measurement report 252 and theassociated information (e.g., the number of cells to report).

Measurement identities may link one measurement object with onereporting configuration. By configuring multiple measurement identities,it is possible to link more than one measurement object to the samereporting configuration. It is also possible to link more than onereporting configuration to the same measurement object. The measurementidentity may be used as a reference number in the measurement report252.

One quantity configuration may be configured per radio access technology(RAT) type. The quantity configuration may define the measurementquantities and the associated filtering used for all event evaluationsand related reporting of that measurement type. One filter may beconfigured per measurement quantity. Measurement gaps may refer toperiods that the user equipment (UE) 204 may use to perform measurements(i.e., no uplink 211 or downlink 209 transmissions are scheduled duringthe measurement gap).

The E-UTRAN may only configure a single measurement object for a givenfrequency. In other words, it is not possible to configure two or moremeasurement objects for the same frequency with different associatedparameters (e.g., different offsets and/or blacklists). The E-UTRAN mayconfigure multiple instances of the same event (e.g., by configuring tworeporting configurations with different thresholds).

The user equipment (UE) 204 may maintain a single measurementconfiguration 250. The measurement configuration 250 may include asingle measurement object list, a single reporting configuration listand a single measurement identities list. The measurement object listmay include measurement objects that are specified per radio accesstechnology (RAT) type. The measurement objects may includeintra-frequency objects (i.e., objects corresponding to the servingfrequencies), inter-frequency objects and inter-RAT objects. Similarly,the reporting configuration list may include E-UTRA and inter-RATreporting configurations. Some reporting configurations may not belinked to a measurement object. Likewise, some measurement objects maynot be linked to a reporting configuration.

The measurement procedures in a measurement configuration 250 maydistinguish between the serving cell(s) 107 (the PCell 107 a and one ormore SCells 107 b if configured for a user equipment (UE) 204 thatsupports carrier aggregation), the listed cells (the cells listed withinthe measurement objects) and detected cells (the cells that are notlisted within the measurement objects but are detected by the userequipment (UE) 204 on the carrier frequencies indicated by themeasurement objects). For E-UTRA, the user equipment (UE) 204 maymeasure and report on the serving cells 107, the listed cells and thedetected cells.

It may be required that the user equipment (UE) 204 be able to identifynew intra-frequency cells and perform reference signal received power(RSRP) measurements of identified intra-frequency cells without anexplicit intra-frequency neighbor cell list that includes the physicallayer cell identities. During the RRC_CONNECTED state, the userequipment (UE) 204 may continuously measure identified intra-frequencycells and search for and identify new intra-frequency cells. It may alsobe required that the user equipment (UE) 204 be able to identify newinter-frequency cells. The user equipment (UE) 204 may perform referencesignal received power (RSRP) measurements of identified inter-frequencycells if carrier frequency information is provided by the PCell 107 a,even if no explicit neighbor list with physical layer cell identities isprovided.

For all measurements performed by the measurement module 249, the userequipment (UE) 204 may apply layer 3 filtering before using the measuredresults for evaluation of reporting criteria and/or for measurementreporting. Whenever the user equipment (UE) 204 has a measurementconfiguration 250, the user equipment (UE) 204 may perform referencesignal received power (RSRP) measurements and reference signal receivedquality (RSRQ) measurements for each serving cell 107.

The user equipment (UE) 204 may perform measurements on the frequenciesand radio access technologies (RATs) indicated in the measurementconfiguration 250 if a measurement gap configuration is setup or if theuser equipment (UE) 204 does not require measurement gaps to perform thespecific measurement. The user equipment (UE) 204 may also performmeasurements on the frequencies and radio access technologies (RATs)indicated in the measurement configuration 250 if s-Measure is notconfigured or if s-Measure is configured and the PCell 107 a referencesignal received power (RSRP) after layer 3 filtering is lower than thevalue of s-Measure.

As discussed above, in Rel-10 radio resource management (RRM)measurement, reference signal received power (RSRP) and reference signalreceived quality (RSRQ) are measured for the cell-specific referencesignal (CRS) but not for the channel state information reference signal(CSI-RS). In Rel-11 radio resource management (RRM) measurement,reference signal received power (RSRP) and/or reference signal receivedquality (RSRQ) are measured for both the cell-specific reference signal(CRS) and the channel state information reference signal (CSI-RS).

For the measurement ID (measId) for which the measurement reportingprocedure was triggered, the user equipment (UE) 204 may set themeasurement results (measResults) within the MeasurementReport messageand submit the MeasurementReport message to lower layers fortransmission from the user equipment (UE) 204 to the E-UTRAN.

The RRCConnectionReconfiguration message is the command to modify an RRCconnection. The RRCConnectionReconfiguration message may conveyinformation for measurement configuration 250, mobility control, radioresource configuration (including resource blocks (RBs), the mediumaccess control (MAC) main configuration and the physical channelconfiguration), any associated dedicated NAS information and securityconfiguration. RRCConnectionReconfiguration is given below:

RRCConnectionReconfiguration-r8-IEs ::= SEQUENCE { measConfig MeasConfigOPTIONAL, - - Need ON mobilityControlInfo MobilityControlInfoOPTIONAL, - - Cond HO dedicatedInfoNASList SEQUENCE (SIZE(1..maxDRB)) OFDedicatedInfoNAS OPTIONAL, -- Cond nonHO radioResourceConfigDedicatedRadioResourceConfigDedicatedOPTIONAL, -- Cond HO-toEUTRAsecurityConfigHO SecurityConfigHO OPTIONAL, -- Cond HOnonCriticalExtension RRCConnectionReconfiguration-v890-IEs OPTIONAL }.

The information element (IE) MeasConfig may specify measurements to beperformed by the user equipment (UE) 204. The information element (IE)MeasConfig may also cover intra-frequency, inter-frequency and inter-RATmobility as well as the configuration of measurement gaps. Theinformation element (IE) MeasConfig is given below:

-- ASN1START MeasConfig ::= SEQUENCE { -- Measurement objectsmeasObjectToRemoveList MeasObjectToRemoveList OPTIONAL, -- Need ONmeasObjectToAddModList MeasObjectToAddModList OPTIONAL, -- Need ON --Reporting configurations reportConfigToRemoveListReportConfigToRemoveList OPTIONAL, -- Need ON reportConfigToAddModListReportConfigToAddModList OPTIONAL, -- Need ON -- Measurement identitiesmeasIdToRemoveList MeasIdToRemoveList OPTIONAL, -- Need ONmeasIdToAddModList MeasIdToAddModList OPTIONAL, -- Need ON -- Otherparameters quantityConfig QuantityConfig OPTIONAL, - - Need ONmeasGapConfig MeasGapConfig OPTIONAL, -- Need ON s-Measure RSRP-RangeOPTIONAL, - - Need ON preRegistrationInfoHRPD PreRegistrationInfoHRPDOPTIONAL, -- Need OP speedStatePars CHOICE { release NULL, setupSEQUENCE { mobilityStateParameters MobilityStateParameters,timeToTrigger-SF SpeedStateScaleFactors } } OPTIONAL, -- Need ON ... }MeasIdToRemoveList ::= SEQUENCE (SIZE (1..maxMeasId)) OF MeasIdMeasObjectToRemoveList ::= SEQUENCE (SIZE (1..maxObjectId)) OFMeasObjectId ReportConfigToRemoveList ::= SEQUENCE (SIZE(1..maxReportConfigId)) OF ReportConfigId -- ASN1STOP.

The information element (IE) MeasId may be used to identify ameasurement configuration 250 (i.e., the linking of a measurement objectand a reporting configuration).

The information element (IE) MeasIdToAddModList concerns a list ofmeasurement identities to add to or modify the measurement configuration250. For each entry in MeasIdToAddModList, the measID, the associatedmeasObjectId and the associated reportConfigId are included. Theinformation element (IE) MeasIdToAddModList is given below:

-- ASN1START MeasIdToAddModList ::= SEQUENCE (SIZE (1..maxMeasId)) OFMeasIdToAddMod MeasIdToAddMod ::=SEQUENCE { measId MeasId, measObjectIdMeasObjectId, reportConfigId ReportConfigId } -- ASN1STOP.

The information element (IE) MeasObjectToAddModList concerns a list ofmeasurement objects to add or modify. The information element (IE)MeasObjectToAddModList may link measObjectId and measObject. Theinformation element (IE) MeasObjectToAddModList is given below:

-- ASN1START MeasObjectToAddModList ::= SEQUENCE (SIZE (1..maxObjectId))OF MeasObjectToAddMod MeasObjectToAddMod ::= SEQUENCE { measObjectIdMeasObjectId, measObject CHOICE { measObjectEUTRA MeasObjectEUTRA,measObjectUTRA MeasObjectUTRA, measObjectGERAN MeasObjectGERAN,measObjectCDMA2000 MeasObjectCDMA2000, ... } } -- ASN1STOP.

The information element (IE) MeasObjectEUTRA specifies informationapplicable for intra-frequency or intra-frequency E-UTRA cells. Theinformation element (IE) MeasObjectEUTRA is given below:

-- ASN1START MeasObjectEUTRA ::= SEQUENCE { carrierFreqARFCN-ValueEUTRA, allowedMeasBandwidth AllowedMeasBandwidth,presenceAntennaPort1 PresenceAntennaPort1, neighCellConfigNeighCellConfig, offsetFreq Q-OffsetRange DEFAULT dB0, -- Cell listcellsToRemoveList CellIndexList OPTIONAL, -- Need ON cellsToAddModListCellsToAddModList OPTIONAL, - - Need ON -- Black listblackCellsToRemoveList CellIndexList OPTIONAL, -- Need ONblackCellsToAddModList BlackCellsToAddModList OPTIONAL, - - Need ONcellForWhichToReportCGI PhysCellId OPTIONAL, - - Need ON ...,[[measCycleSCell-r10 MeasCycleSCell-r10 OPTIONAL, -- Need ONmeasSubframePatternConfigNeigh-r10 MeasSubframePatternConfigNeigh-r10OPTIONAL -- Need ON ]] } CellsToAddModList ::= SEQUENCE (SIZE(1..maxCellMeas)) OF CellsToAddMod CellsToAddMod ::= SEQUENCE {cellIndex INTEGER (1..maxCellMeas), physCellId PhysCellId,cellIndividualOffset Q-OffsetRange } BlackCellsToAddModList ::= SEQUENCE(SIZE (1..maxCellMeas)) OF BlackCellsToAddMod BlackCellsToAddMod ::=SEQUENCE { cellIndex INTEGER (1..maxCellMeas), physCellIdRangePhysCellIdRange } MeasCycleSCell-r10 ::= ENUMERATED {sf160, sf256,sf320, sf512, sf640, sf1024, sf1280, spare1}MeasSubframePatternConfigNeigh-r10 ::= CHOICE { release NULL, setupSEQUENCE { measSubframePatternNeigh-r10 MeasSubframePattern-r10,measSubframeCellList-r10 MeasSubframeCellList-r10 OPTIONAL -- CondmeasSubframe } } MeasSubframeCellList-r10 ::= SEQUENCE (SIZE(1..maxCellMeas)) OF PhysCellIdRange -- ASN1STOP.

The information element (IE) ReportConfigEUTRA specifies criteria fortriggering an E-UTRA measurement reporting event. The trigger type maybe set to event trigger or periodic trigger. The E-UTRA measurementreporting events are listed below:

-   Event A1: Serving becomes better than absolute threshold;-   Event A2: Serving becomes worse than absolute threshold;-   Event A3: Neighbour becomes amount of offset better than PCell;-   Event A4: Neighbour becomes better than absolute threshold;-   Event A5: PCell becomes worse than absolute threshold1 AND Neighbour    becomes better than another absolute threshold2;-   Event A6: Neighbour becomes amount of offset better than SCell.    The information element (IE) ReportConfigEUTRA is given below:

-- ASN1START ReportConfigEUTRA ::= SEQUENCE { triggerType CHOICE { eventSEQUENCE { eventId CHOICE { eventA1 SEQUENCE { a1-ThresholdThresholdEUTRA }, eventA2 SEQUENCE { a2-Threshold ThresholdEUTRA },eventA3 SEQUENCE { a3-Offset INTEGER (−30..30), reportOnLeave BOOLEAN },eventA4 SEQUENCE { a4-Threshold ThresholdEUTRA }, eventA5 SEQUENCE {a5-Threshold1 ThresholdEUTRA, a5-Threshold2 ThresholdEUTRA }, ...,eventA6-r10 SEQUENCE { a6-Offset-r10 INTEGER (−30..30),a6-ReportOnLeave-r10 BOOLEAN } }, hysteresis Hysteresis, timeToTriggerTimeToTrigger }, periodical SEQUENCE { purpose ENUMERATED {reportStrongestCells, reportCGI} } }, triggerQuantity ENUMERATED {rsrp,rsrq}, reportQuantity ENUMERATED {sameAsTriggerQuantity, both},maxReportCells INTEGER (1..maxCellReport), reportIntervalReportInterval, reportAmount ENUMERATED {r1, r2, r4, r8, r16, r32, r64,infinity}, ..., [[ si-RequestForHO-r9 ENUMERATED {setup} OPTIONAL, - -Cond reportCGI ue-RxTxTimeDiffPeriodical-r9 ENUMERATED {setup}OPTIONAL - - Need OR ]], [[ includeLocationInfo-r10 ENUMERATED {true}OPTIONAL, - - Cond reportMDT reportAddNeighMeas-r10 ENUMERATED {setup}OPTIONAL -- Need OR ]] } ThresholdEUTRA ::= CHOICE{ threshold-RSRPRSRP-Range, threshold-RSRQ RSRQ-Range } -- ASN1STOP.

The information element (IE) ReportConfigId may be used to identify ameasurement reporting configuration. The information element (IE)MeasResults covers measured results for intra-frequency, inter-frequencyand inter-RAT mobility. The information element (IE) MeasResults mayinclude measId, the measurement results of PCell 107 a and optionallythe measurement results of the neighbor cell and the SCells 107 b.

The user equipment (UE) 204 may include a variable VarMeasConfig. Thevariable VarMeasConfig is discussed in additional detail below inrelation to FIG. 8. The variable VarMeasConfig may include theaccumulated configuration of the measurements to be performed by theuser equipment (UE) 204, including intra-frequency, inter-frequency andinter-RAT mobility related measurements. The VarMeasConfig variable isgiven below:

-- ASN1START VarMeasConfig ::= SEQUENCE { -- Measurement identitiesmeasIdList MeasIdToAddModList OPTIONAL, -- Measurement objectsmeasObjectList MeasObjectToAddModList OPTIONAL, -- Reportingconfigurations reportConfigList ReportConfigToAddModList OPTIONAL, --Other parameters quantityConfig QuantityConfig OPTIONAL, s-MeasureINTEGER (−140..−44) OPTIONAL, speedStatePars CHOICE { release NULL,setup SEQUENCE { mobilityStateParameters MobilityStateParameters,timeToTrigger-SF SpeedStateScaleFactors } } OPTIONAL } -- ASN1STOP.

The user equipment (UE) 204 may also include a variableVarMeasReportList. The variable VarMeasReportList is discussed inadditional detail below in relation to FIG. 9. The variableVarMeasReportList may include information about the measurements forwhich the triggering conditions have been met. The VarMeasReportListvariable is given below:

-- ASN1START VarMeasReportList ::= SEQUENCE (SIZE (1..maxMeasId)) OFVarMeasReport VarMeasReport ::= SEQUENCE { -- List of measurement thathave been triggered measId MeasId, cellsTriggeredList CellsTriggeredListOPTIONAL, numberOfReportsSent INTEGER } CellsTriggeredList ::= SEQUENCE(SIZE (1..maxCellMeas)) OF CHOICE { physCellIdEUTRA PhysCellId,physCellIdUTRA CHOICE { fdd PhysCellIdUTRA-FDD, tdd PhysCellIdUTRA-TDD}, physCellIdGERAN SEQUENCE { carrierFreq CarrierFreqGERAN, physCellIdPhysCellIdGERAN }, physCellIdCDMA2000 PhysCellIdCDMA2000 } -- ASN1STOP.

The channel state information (CSI) related radio resource control (RRC)configuration may be defined for the purpose of channel quality and/orchannel state measurements. The user equipment (UE) 204 may report thechannel state information (CSI) in the physical layer. Depending on thereporting mode, either the cell-specific reference signal (CRS) or thechannel state information reference signal (CSI-RS) is used for thechannel state information (CSI) measurement. The E-UTRAN may provide theCQI report configuration (CQI-ReportConfig) and the CSI-RS configuration(CSI-RS-Config) applicable for a user equipment (UE) 204 inRRC_CONNECTED using dedicated signaling (i.e., using theradioResourceConfigDedicated in the RRCConnectionReconfigurationmessage).

The information element (IE) CSI-RS-Config may be used to specify thechannel state information (CSI) reference signal configuration. Theinformation element (IE) CSI-RS-Config may include configurations forthe number of antenna ports for CSI-RS, the physical resource forCSI-RS, the subframes for CSI-RS, etc. The information element (IE)CQI-ReportConfig may be used to specify the CQI reporting configurationof a user equipment (UE) 204.

Once the user equipment (UE) 204 has generated a measurement report 252,the user equipment (UE) 204 may use the feedback module 251 to transmitthe measurement report 252 to the E-UTRAN.

FIG. 3 is a block diagram illustrating the layers used by a userequipment (UE) 304. The user equipment (UE) 304 of FIG. 3 may be oneconfiguration of the user equipment (UE) 104 of FIG. 1. The userequipment (UE) 304 may include a radio resource control (RRC) layer 353,a radio link control (RLC) layer 354, a medium access control (MAC)layer 355 and a physical (PHY) layer 356. From the physical (PHY) layer356, each of the radio resource control (RRC) layer 353, the radio linkcontrol (RLC) layer 354 and the medium access control (MAC) layer 355may be referred to as higher layers 114. The user equipment (UE) 304 mayinclude additional layers not shown in FIG. 3.

FIG. 4 is a block diagram illustrating a homogenous network 400 withintra-site coordinated multipoint (CoMP). Each eNB 402 a-g may operatethree cells. Each eNB 402 a-g may transmit downlink signals for thethree cells. The coordination area for this homogenous network 400 isthree cells for each eNB 402.

FIG. 5 is a block diagram illustrating a homogenous network 500 withhigh Tx power remote radio heads (RRHs) 559 a-f. Each remote radio head(RRH) 559 and an eNB 502 may also be referred to as a point. The eNB 502may operate 21 cells using six remote radio heads (RRHs) 559. Eachremote radio head (RRH) 559 and the eNB 502 may transmit downlinksignals for the three cells associated with the remote radio head (RRH)559. Each remote radio head (RRH) 559 may be coupled to the eNB 502 viaan optical fiber 558. The coordination area for this homogenous network500 is 21 cells.

FIG. 6 is a block diagram illustrating a network 600 with low Tx powerremote radio heads (RRHs) 659 a-f within the macrocell 657 coverage.Each remote radio head (RRH) 659 and an eNB 602 may also be referred toas a point. The macrocell 657 may include an eNB 602 coupled to multiplelow Tx power remote radio heads (RRHs) 659 (also referred to asOmni-antennas) via optical fibers 658. The eNB 602 operates onemacrocell 657 and six areas using the six remote radio heads (RRHs) 659.The coordination area for this heterogeneous network is one macrocell657 and six areas.

The transmission/reception points created by the remote radio heads(RRHs) 659 may have the same cell ID as the macrocell 657 or differentcell IDs from the macrocell 657. When the transmission/reception pointscreated by the remote radio head (RRH) 659 have the same cell IDs as themacrocell 657, it is commonly understood that all the transmissionpoints transmit the same cell-specific reference signal (CRS) but cantransmit different channel state information reference signals(CSI-RSs).

FIG. 7 is a block diagram illustrating a generalized coordinatedmultipoint (CoMP) architecture 700. Multiple coordinated multipoint(CoMP) measurement sets 762 may be used for user equipment (UE) 104. Forexample, a coordinated multipoint (CoMP) cooperating set may be a set ofgeographically separated points directly and/or indirectly participatingin data transmission to a user equipment (UE) 104 in a time-frequencyresource. The coordinated multipoint (CoMP) cooperating set may or maynot be transparent to the user equipment (UE) 104.

The coordinated multipoint (CoMP) transmission points 760 a-n may be apoint or set of points transmitting data to a user equipment (UE) 104.The coordinated multipoint (CoMP) transmission points 760 are a subsetof the coordinated multipoint (CoMP) cooperating set. A coordinatedmultipoint (CoMP) measurement set 762 may be the set of points aboutwhich channel state/statistical information related to their link to theuser equipment (UE) 104 is measured and/or reported at L1 (PUCCH). Aradio resource management (RRM) measurement set 763 may be the set ofcells for which radio resource management (RRM) measurements areperformed. The radio resource management (RRM) measurement set 763 isalready defined in Rel-8. Additional radio resource management (RRM)measurement methods (such as coordinated multipoint (CoMP) radioresource management (RRM) measurement) may be considered (e.g., in orderto separate different points belonging to the same logical cell entityor in order to select the coordinated multipoint (CoMP) measurement set762). The additional radio resource management (RRM) measurement set 763may be referred to as the coordinated multipoint (CoMP) radio resourcemanagement (RRM) measurement set 763.

In the generalized coordinated multipoint (CoMP) architecture 700, fastcoordination coordinated multipoint (CoMP) schemes (e.g., JT, DPS,CS/CB) may be used only for intra-eNB communications while slowercoordination coordinated multipoint (CoMP) schemes (e.g., CS/CB) may beused for inter-eNB communications. In Rel-11, only control informationmay be transmitted over X2 761 a-b; no data may be transported over X2761. Proprietary inter-eNB interfaces may be used to provide fasterschemes for inter-eNB communication (especially in cases of co-locatedeNBs 702 a-c). Since the user equipment (UE) 104 only knows cells (andnot eNBs 702), this has no impact on the user equipment (UE) 104.

While the network may be aware of all the coordinated multipoint (CoMP)measurement sets 762, the user equipment (UE) 104 may only know of twocoordinated multipoint (CoMP) measurement sets 762: the coordinatedmultipoint (CoMP) measurement set 762 and the radio resource management(RRM) measurement set 763.

The coordinated multipoint (CoMP) measurement may be based on a channelstate information reference signal (CSI-RS) measurement. This is becausea CRS-based radio resource management (RRM) measurement will not workwhen the transmission/reception points created by remote radio heads(RRHs) 659 have the same cell ID as the macrocell 657 (as illustratedabove in relation to FIG. 6), the transmission points 760 are notdistinguishable to the user equipment (UE) 104 using the cell-specificreference signal (CRS). Using the channel state information referencesignal (CSI-RS), the reference signal received power (RSRP) andreference signal received quality (RSRQ) may still be measured (referredto as the CSI-RSRP and the CSI-RSRQ). The CSI-RSRP and the CSI-RSRQ maybe used by the network to determine which transmission points 760 shouldbe included in the coordinated multipoint (CoMP) measurement set 762(e.g., addition, removal, replacement). Inter-cell handover may not beone of the purposes of the coordinated multipoint (CoMP) radio resourcemanagement (RRM) measurement.

The measurement of the CSI-RSRP and the CSI-RSRQ needs to be defined.Currently, the channel state information reference signal (CSI-RS) isused for channel state information (CSI) measurement but not forcoordinated multipoint (CoMP) radio resource management (RRM)measurement. The CSI-RSRP and the CSI-RSRQ measurements may also be usedfor mobility purposes.

FIG. 8 is a block diagram illustrating the structure of a measurementconfiguration variable 864. The measurement configuration variable 864may be referred to as VarMeasConfig. Both the user equipment (UE) 104and the eNB 102 may maintain the measurement configuration variable 864.The measurement configuration variable 864 may include a list ofmeasurement IDs 865 a-c, a list of measurement objects 866 and a list ofreport configurations 867. The list of measurement IDs 865 may includeone or more measurement IDs 878 a-c, one or more measurement object IDs879 a-c and one or more report configuration IDs 880 a-c. Eachmeasurement ID 878 may be linked to a measurement object ID 879 and areport configuration ID 880.

FIG. 9 is a block diagram illustrating the structure of a measurementreport list 968. The measurement report list 968 may be referred to asVarMeasReportList. Both the user equipment (UE) 104 and the eNB 102 maymaintain the measurement report list 968. The measurement report list968 may include multiple measurement reports 969 a-c. Each measurementreport 969 may include the measurement ID 978 a-c and the list of cellsthat triggered the measurement report 969.

FIG. 10 is a block diagram illustrating an RRC ConnectionReconfiguration message 1070 structure. The RRC ConnectionReconfiguration message 1070 may be referred to asRRCConnectionReconfiguration. The RRC Connection Reconfiguration message1070 may include measurement configurations 1071 and the radio resourcesdedicated 1072.

FIG. 11 is a flow diagram of a method 1100 for coordinated multipoint(CoMP) radio resource management (RRM) measurement. The method 1100 maybe performed by a user equipment (UE) 104. The user equipment (UE) 104may keep a single measurement object 879 in a carrier frequency. Themeasurement object 879 may include a set of CSI-RS configurations in ameasurement configuration 250 for the measurement of CSI-RSRP and/orCSI-RSRQ in the radio resource control (RRC) layer. The measurementobject 879 may also include a set of CSI-RS configurations in a radioresource configuration for channel quality measurement and/or reportingin the physical layer. The measurement object 879 may further include asignal to indicate whether the measurement object 879 is concerned withthe cell-specific reference signal (CRS) or the channel stateinformation reference signal (CSI-RS) in a report configuration 880.

The user equipment (UE) 104 may receive 1102 a measurement configuration250 from a network. In one configuration, the user equipment (UE) 104may receive a measurement configuration 250 from an eNB 102. Using themeasurement configuration 250, the user equipment (UE) 104 may generate1104 a measurement report 252. More specifically, the user equipment(UE) 104 may generate coordinated multipoint (CoMP) radio resourcemanagement (RRM) measurements using the channel state informationreference signal (CSI-RS) in addition to radio resource management (RRM)measurements using the cell-specific reference signal (CRS). The userequipment (UE) 104 may then send 1106 the measurement report 252 to thenetwork.

FIG. 12 is a flow diagram of a method for coordinating a coordinatedmultipoint (CoMP) radio resource management (RRM) measurement. Themethod 1200 may be performed by the network. For example, the method1200 may be performed by an eNB 102. The network may determine 1202radio resource management (RRM) measurement settings for a userequipment (UE) 104. The network may generate 1204 a measurementconfiguration 250 for the user equipment (UE). More specifically, thenetwork may generate coordinated multipoint (CoMP) radio resourcemanagement (RRM) measurement settings using the channel stateinformation reference signal (CSI-RS) in addition to radio resourcemanagement (RRM) measurement settings using the cell-specific referencesignal (CRS). The network may then send 1206 the measurementconfiguration to the user equipment (UE).

FIG. 13 illustrates the transmission of a measurement configuration 1350from an eNB 1302 to a user equipment (UE) 1304. The measurementconfiguration 1350 may include one or more measurement objects 1373.Each measurement object 1373 may include a set of CSI-RS configurations1374. In one configuration, the measurement configuration 1350 mayinstruct the user equipment (UE) 1304 to change settings to measurementobjects 1373. For example, the measurement configuration may instructthe user equipment (UE) 1304 to add, modify or remove CSI-RSconfigurations 1374 from the set of CSI-RS configurations 1374.

FIG. 14 is a block diagram illustrating an independent configuration forthe channel state information reference signal (CSI-RS). To definechannel state information reference signal (CSI-RS) based radio resourcemanagement (RRM) measurement, one or more sets of CSI-RS configurations1374 are included in a measurement object 1373 configuration. Similar toa cell list (or neighbor cell list), the information element (IE) to addand modify a list of CSI-RS configurations 1374 and the informationelement (IE) to remove CSI-RS configurations 1374 may be included in ameasurement object 1373. The eNB 102 may only configure a singlemeasurement object 1373 for a given frequency.

Each measurement object 1373 may be specific to a carrier frequency andcorrespond to a cell-specific reference signal (CRS) based radioresource management (RRM) measurement (i.e., a normal radio resourcemanagement (RRM) measurement) in the carrier frequency. If the channelstate information reference signals (CSI-RSs) are configured in themeasurement object in the carrier frequency of a serving cell, themeasurement object 1373 may also correspond to a channel stateinformation reference signal (CSI-RS) based radio resource management(RRM) measurement (i.e., a coordinated multipoint (CoMP) radio resourcemanagement (RRM) measurement) in the carrier frequency of the servingcell. A channel state information reference signal (CSI-RS) radioresource management (RRM) measurement may be performed in the servingcell(s) where channel state information reference signals (CSI-RSs) areconfigured. Thus, one measurement object in one carrier frequency may beused.

As an example, in the measurement objects of a list 1475 of measurementobjects to add, a list of CSI-RS configurations 1374 is included. TheseCSI-RS configurations 1374 may be used for channel state informationreference signal (CSI-RS) based radio resource management (RRM)measurement. Independently, the list of CSI-RS configurations 1374 maybe included in the physical configuration for a PCell and/or SCells. Inthe physical configuration of the radio resource configuration 1476, aCQI report configuration (cqi-ReportConfig-r11) in each serving cell maycorrespond to each CSI-RS configuration 1374 (csi-RS-Config-r11) in eachserving cell. In one configuration, multiple csi-RS-Config-r11s may belinked to one cqi-ReportConfig-r11. In another configuration, multiplecqi-ReportConfig-R11s may be configured in each serving cell and eachcsi-RS-Config-r11 may be linked to each cqi-ReportConfig-R11.

Using an independent configuration for channel state informationreference signal (CSI-RS) allows an eNB 102 to configure radio resourcemanagement (RRM) measurement and physical layer measurementindependently. There may be no need to fix a coordinated multipoint(CoMP) measurement set 762 to a subset of a coordinated multipoint(CoMP) radio resource management (RRM) measurement set 763.

FIG. 15 is a block diagram illustrating an independent configuration forchannel state information reference signal (CSI-RS). The list of CSI-RSconfigurations 1374 may be included in a measurement object 1373. TheCSI-RS configurations 1374 may be used by the user equipment (UE) 104for a channel state information reference signal (CSI-RS) based radioresource management (RRM) measurement (i.e., coordinated multipoint(CoMP) radio resource management (RRM) measurement). For coordinatedmultipoint (CoMP) measurement, some of the CSI-RS configurations 1374may be associated with csi-RS-Config-r11(s) (i.e., the channel stateinformation reference signal (CSI-RS) indexes) that are configured inthe physical configuration in each serving cell.

A command to add measurement objects to a list (measObjectToAddModList1575) is shown. Multiple csi-RS-Config-r11s in a measurement object 879may be linked to one cqi-ReportConfig-r11 in a physical configuration ofa radio resource configuration 1576. In one configuration, multiplecqi-ReportConfig-r11s may be configured in each serving cell and eachcsi-RS-Config-r11 may be linked to each cqi-ReportConfig-r11. The eNB102 may reduce overhead by avoiding multiple configurations of thechannel state information reference signal (CSI-RS) for the radioresource management (RRM) measurement and the physical layermeasurement. The coordinated multipoint (CoMP) measurement set 762 maythen become a subset of the coordinated multipoint (CoMP) radio resourcemanagement (RRM) measurement set 763.

FIG. 16 is a block diagram illustrating a configuration for channelstate information reference signal (CSI-RS) in the physicalconfiguration. More specifically, a command to add measurement objects1373 to a list of measurement objects 1373 (measObjectToAddModList 1675)is illustrated along with the radio resource configuration 1676. Todefine a channel state information reference signal (CSI-RS) based radioresource management (RRM) measurement, one or more sets of CSI-RSconfigurations 1374 may be included in a physical configuration. If ameasurement configuration 250 defines channel state informationreference signal (CSI-RS) based radio resource management (RRM) and themeasurement configuration 250 is associated with a measurement object1373, the CSI-RS configurations 1374 of the carrier frequency of themeasurement object 1373 may be used for a coordinated multipoint (CoMP)radio resource management (RRM) measurement. An information element (IE)to add and modify a list of CSI-RS configurations 1374 and aninformation element (IE) to remove CSI-RS configurations 1374 may beincluded in the physical configuration. Each measurement object 1373 maybe specific to a carrier frequency and correspond to a cell-specificreference signal (CRS) based radio resource management (RRM) measurementin the carrier frequency.

If the channel state information reference signals (CSI-RSs) areconfigured in a physical configuration of a serving cell, themeasurement object 1373 of the carrier frequency of the serving cell mayalso correspond to channel state information reference signal (CSI-RS)based radio resource management (RRM) measurement (i.e., coordinatedmultipoint (CoMP) radio resource management (RRM) measurement) in thecarrier frequency of the serving cell. Coordinated multipoint (CoMP)radio resource management (RRM) measurement may be performed in servingcells where channel state information reference signals (CSI-RSs) areconfigured. Using the configuration for channel state informationreference signal (CSI-RS) in the physical configuration may allow foronly one measurement object 1373 in one carrier frequency to be used.

The list of CSI-RS configurations 1374 may be included in the physicalconfiguration of each serving cell. The CSI-RS configurations 1374 maybe used for coordinated multipoint (CoMP) radio resource management(RRM) measurement. Some of the CSI-RS configurations 1374 may be usedfor the coordinated multipoint (CoMP) measurement set 762, which is usedfor a channel state information (CSI) report in the physical layer. Thecqi-ReportConfig-r11s in each serving cell may correspond to some of thecsi-RS-Config-r11s configured in the physical configuration in eachserving cell.

Multiple csi-RS-Config-r11s may be linked to one cqi-ReportConfig-r11.In one configuration, multiple cqi-ReportConfig-r11s may be configuredin each serving cell and each csi-RS-Config-r11 may be linked to eachcqi-ReportConfig-r11. The eNB 102 may reduce overhead by avoidingmultiple configurations of the channel state information referencesignal (CSI-RS) for the radio resource management (RRM) measurement andthe physical layer measurement. The coordinated multipoint (CoMP)measurement set 762 may then become a subset of the coordinatedmultipoint (CoMP) radio resource management (RRM) measurement set 763.

FIG. 17 is a block diagram illustrating a measurement object 1373 andindependent configuration for channel state information reference signal(CSI-RS). More specifically, a command to add measurement objects 1373to a list of measurement objects 1373 (measObjectToAddModList 1775) isillustrated along with the radio resource configuration 1776. To definechannel state information reference signal (CSI-RS) based radio resourcemanagement (RRM) measurement, sets of CSI-RS configurations 1374 may beincluded in a measurement object configuration.

An information element (IE) to add and modify a list of CSI-RSconfigurations 1374 and an information element (IE) to remove CSI-RSconfigurations 1374 may be included in a measurement object 1373, whichis different than a measurement object 1373 for cell-specific referencesignal (CRS) based radio resource management (RRM) measurement in acarrier frequency. The eNB 102 may configure a single measurement object1373 for cell-specific reference signal (CRS) based radio resourcemanagement (RRM) measurement for a given frequency and a singlemeasurement object 1373 for channel state information reference signal(CSI-RS) based radio resource management (RRM) measurement for a givenfrequency. Each measurement object 1373 may be specific to a carrierfrequency and correspond to cell-specific reference signal (CRS) basedradio resource management (RRM) measurement in the carrier frequency orchannel state information reference signal (CSI-RS) based radio resourcemanagement (RRM) measurement in the carrier frequency. If themeasurement ID (measID) 878 links to a measurement object 879 forCSI-RS, channel state information reference signal (CSI-RS) based radioresource management (RRM) measurement may be performed in the servingcells. The RRC may then keep existing cell-specific reference signal(CRS) based radio resource management (RRM) measurements as currentlydefined while also managing channel state information reference signal(CSI-RS) based radio resource management (RRM) measurement.

A list of CSI-RS configurations 1374 may be included in a newmeasurement object 1373 in a carrier frequency of a serving cell. TheCSI-RS configurations 1374 may be used for channel state informationreference signal (CSI-RS) based radio resource management (RRM)measurement. The list of CSI-RS configurations 1374 for a coordinatedmultipoint (CoMP) measurement set 672 may be included in the physicalconfiguration of a PCell and/or SCells. The coordinated multipoint(CoMP) measurement set 672 may be used for the channel state information(CSI) report in the physical layer.

One or more cqi-ReportConfig-r11s in each serving cell may correspond toone or more csi-RS-Config-r11s configured in the physical configurationin each serving cell. Multiple csi-RS-Config-r11s may be linked to onecqi-ReportConfig-r11. In one configuration, multiplecqi-ReportConfig-r11s may be configured in each serving cell and eachcsi-RS-Config-r11 may be linked to each cqi-ReportConfig-r11.

FIG. 18 is a block diagram illustrating how a report configuration 1880a-c may indicate that a measurement ID 1878 a-c in a measurementconfiguration 1850 is cell-specific reference signal (CRS) based orchannel state information reference signal (CSI-RS) based. Eachmeasurement ID (measID) 1878 a-c may be linked to either cell-specificreference signal (CRS) or channel state information reference signal(CSI-RS). In Rel-10, measID 1878 may only be linked to cell-specificreference signal (CRS) based radio resource management (RRM)measurements. When a measurement ID 1878 is signaled, the measurement ID1878 may be associated with a measurement object ID 1879 a-c and areport configuration ID 1880 a-c.

When sets of CSI-RS configurations 1374 are included in a measurementobject configuration or a physical configuration, the measurement object1850 does not specify whether it is for cell-specific reference signal(CRS) or channel state information reference signal (CSI-RS). Therefore,each report configuration 1880 may include an indication of whether thereport configuration 1880 is for cell-specific reference signal (CRS) orchannel state information reference signal (CSI-RS). The indication inthe report configuration 1880 may be one or more new event identitieswith a different identity than other cell-specific reference signal(CRS) based events. An event identity may identify measurement reportingevents (i.e., the current list of events A1-A6 is discussed above inrelation to FIG. 2). Events A1-A6 are defined as events based onmeasurement results of the cell-specific reference signal (CRS) of theserving cell and/or the neighbor cell. In addition, events based on themeasurement results of the channel state information reference signals(CSI-RSs) (of the serving cell and/or the neighbor cell) and/or thecell-specific reference signal (CRS) (of the serving cell and/or theneighbor cell) may be used.

The indication may instead be an explicit indication {CRS, CSI-RS}. Theexplicit indication may be {CRS, CSI-RS, both}, where “both” means boththe cell-specific reference signal (CRS) and the channel stateinformation reference signals (CSI-RSs). The explicit indication may beadd-CSI-RS-report {setup} to indicate whether the measurement reportshould include the measurement results of CSI-RS(s). When a measurementID (measID) 1878 is signaled, a measurement object (measObject) 1879 anda report configuration (reportConfig) 1880 are associated with themeasurement ID 1878. Therefore, the report configuration 1880 can definewhether the measurement ID 1878 is for channel state informationreference signal (CSI-RS) based radio resource management (RRM)measurement or cell-specific reference signal (CRS) based radio resourcemanagement (RRM) measurement. An explicit or implicit indication mayalso be used in configurations where sets of CSI-RS configurations 1374are included in a measurement object configuration.

FIG. 19 is a block diagram illustrating how a measurement object 1979a-c may indicate that a measurement ID 1978 a-c in a measurementconfiguration 1950 is for cell-specific reference signal (CRS) orchannel state information reference signal (CSI-RS). Each measurement ID(measID) 1978 may be linked to either cell-specific reference signal(CRS) or channel state information reference signal (CSI-RS). When ameasurement ID 1978 is signaled, the measurement ID 1978 may beassociated with a measurement object ID 1979 and a report configurationID 1980 a-c. In one configuration, whether the measurement object 1979is associated with the cell-specific reference signal (CRS) or thechannel state information reference signal (CSI-RS) may identify whetherthe measurement ID 1978 is for cell-specific reference signal (CRS)based radio resource management (RRM) measurement and/or for channelstate information reference signal (CSI-RS) based radio resourcemanagement (RRM) measurement.

The quantities of the PCell 107 a (RSRP and/or RSRQ) are included in theradio resource management (RRM) measurement report 122. The quantitiesof the SCell(s) 107 b are included in the radio resource management(RRM) measurement report 122 if the SCell(s) 107 b are configured (i.e.if the carrier aggregation is configured). The quantities of CSI-RS(s)of the PCell 107 a (CSI-RSRP and/or CSI-RSRP) may also be included inthe radio resource management (RRM) measurement report 122. Thequantities of CSI-RS(s) of the SCell(s) 107 b may be included in theradio resource management (RRM) measurement report 122 if the SCell(s)107 b are configured. Therefore, one radio resource management (RRM)measurement report 122 may include the quantities of the PCell 107 a,the quantities of the SCell(s) 107 b, the quantities of CSI-RS(s) of thePCell 107 a and/or the quantities of CSI-RS(s) of the SCell(s) 107 b.One radio resource management (RRM) measurement report 122 may includethe quantities of each of multiple CSI-RSs in one serving cell. Oneradio resource management (RRM) measurement report 122 may also includethe quantities of each of multiple-CSI-RSs in each of multiple servingcells.

Conditions when the quantities of CSI-RS(s) are included in themeasurement result may be further defined. One example is to include thequantities of any of the configured (or listed) CSI-RS(s) of any servingcell(s) whenever CSI-RS(s) are configured in a measurement configuration250. Another example is to include the quantities of any of theconfigured (or listed) CSI-RS(s) of any serving cell(s) whenever ameasurement object associated with a concerned measID includes a CSI-RS.Yet another example is to include the quantities of any of theconfigured (or listed) CSI-RS(s) of serving cell(s) corresponding to acarrier frequency of a measurement object whenever the measurementobject associated with a concerned measID includes a CSI-RS. Yet anotherexample is to include the quantities of any of the configured (orlisted) CSI-RS(s) of any of the serving cell(s) whenever a reportconfiguration (or a measurement event type) associated with a concernedmeasID is related to a CSI-RS. Yet another example is to include thequantities of any of the configured (or listed) CSI-RS(s) of servingcell(s) corresponding to a carrier frequency of a measurement objectthat corresponds to a measID whenever a report configuration (or ameasurement event type) associated with the concerned measID is relatedto a CSI-RS.

Another example is to include the quantities of the best configured (orlisted) CSI-RS(s) of any serving cell(s) (up to a maximum reportingnumber of CSI-RS(s)) whenever CSI-RS(s) are configured in a measurementconfiguration 250. The maximum reporting number of CSI-RSs may beconfigured in a report configuration. Yet another example is to includethe quantities of the best configured (or listed) CSI-RS(s) of anyserving cell(s) (up to a maximum reporting number of CSI-RS(s)) whenevera measurement object associated with a concerned measID includes aCSI-RS. Another example is to include the quantities of the bestconfigured (or listed) CSI-RS(s) of serving cell(s) (up to a maximumreporting number of CSI-RS(s)) corresponding to a carrier frequency of ameasurement object whenever the measurement object associated with aconcerned measID includes a CSI-RS. Yet another example is to includethe quantities of the best configured (or listed) CSI-RS(s) of any ofthe serving cell(s) (up to a maximum reporting number of CSI-RS(s))whenever a report configuration (or a measurement event type) associatedwith a concerned measID is related to a CSI-RS. Yet another example isto include the quantities of any of the best configured (or listed)CSI-RS(s) of serving cell(s) (up to a maximum reporting number ofCSI-RS(s)) corresponding to a carrier frequency of a measurement objectthat correponds to a measID whenever a report configuration (or ameasurement event type) associated with the concerned measID is relatedto a CSI-RS. For those examples, the best configured (or listed)CSI-RS(s) may be listed in each serving cell and may be decided by theuser equipment (UE) 104 based on the reference signal received power(RSRP) and/or reference signal received quality (RSRQ) of the configured(or listed) CSI-RS(s) measured in each serving cell.

Another example is to include the quantities of CSI-RS(s) of any servingcell(s) that fulfilled a trigger condition whenever CSI-RS(s) areconfigured in a measurement configuration 250. Yet another example is toinclude the quantities of CSI-RS(s) of any serving cell(s) thatfulfilled a trigger condition whenever a measurement object associatedwith a concerned measID includes a CSI-RS. Another example is to includethe quantities of CSI-RS(s) of any serving cell(s) that fulfilled atrigger condition corresponding to a carrier frequency of a measurementobject whenever the measurement object associated with a concernedmeasID includes a CSI-RS. Yet another example is to include thequantities of CSI-RS(s) of any serving cell(s) that fulfilled a triggercondition whenever a report configuration (or a measurement event type)associated with a concerned measID is related to a CSI-RS.

Yet another example is to include the quantities of CSI-RS(s) of servingcell(s) that fulfilled a trigger condition corresponding to a carrierfrequency of a measurement object that corresponds to a measID whenevera report configuration (or a measurement event type) associated with theconcerned measID is related to a CSI-RS. For those examples, whether thetrigger condition is fulfilled or not may be decided in each servingcell by the user equipment (UE) 104 based on the reference signalreceived power (RSRP) and/or reference signal received quality (RSRQ) ofa CSI-RS measured in each serving cell.

By these methods, one benefit is that the eNB 102 and the user equipment(UE) 104 can operate efficiently and sustainably in scenarios whereCSI-RS based radio resource management (RRM) measurement is used inaddition to CRS based radio resource management (RRM) measurement. TheeNB 102 can measure more detail of the channels associated with the userequipment (UE) 104. Also CSI-RS based radio resource management (RRM)measurement can be used even when multiple serving cells are configured.

The cell-specific reference signal (CRS) may also be referred to as thecommon reference signal (RS). The coordinated multipoint (CoMP) radioresource management (RRM) measurement set 763 may also be referred to asthe coordinated multipoint (CoMP) Resource management Set (CRMS). Theradio resource management (RRM) measurement report 122 may also bereferred to as the measurement report or the measurement report in theradio resource control (RRC) layer 353. The CSI-RSRP may also bereferred to as the CSI-RS RSRP. The CSI-RSRQ may also be referred to asthe CSI-RS RSRQ. Further, the various names used for the describedparameters and signal elements (e.g., CSI-RS, CRS, csi-RS-Config-r11,etc.) are not intended to be limiting in any respect, as theseparameters and signal elements may be identified by any suitable names.

FIG. 20 illustrates various components that may be utilized in a userequipment (UE) 2004. The user equipment (UE) 2004 may be utilized as theuser equipment (UE) 104 illustrated previously. The user equipment (UE)2004 includes a processor 2087 that controls operation of the userequipment (UE) 2004. The processor 2087 may also be referred to as aCPU. Memory 2081, which may include both read-only memory (ROM), randomaccess memory (RAM) or any type of device that may store information,provides instructions 2082 a and data 2083 a to the processor 2087. Aportion of the memory 2081 may also include non-volatile random accessmemory (NVRAM). Instructions 2082 b and data 2083 b may also reside inthe processor 2087. Instructions 2082 b and/or data 2083 b loaded intothe processor 2087 may also include instructions 2082 a and/or data 2083a from memory 2081 that were loaded for execution or processing by theprocessor 2087. The instructions 2082 b may be executed by the processor2087 to implement the systems and methods disclosed herein.

The user equipment (UE) 2004 may also include a housing that contains atransmitter 2040 and a receiver 2038 to allow transmission and receptionof data. The transmitter 2040 and receiver 2038 may be combined into atransceiver 2037. One or more antennas 2012 a-n are attached to thehousing and electrically coupled to the transceiver 2037.

The various components of the user equipment (UE) 2004 are coupledtogether by a bus system 2086, which may include a power bus, a controlsignal bus, and a status signal bus, in addition to a data bus. However,for the sake of clarity, the various buses are illustrated in FIG. 20 asthe bus system 2086. The user equipment (UE) 2004 may also include adigital signal processor (DSP) 2084 for use in processing signals. Theuser equipment (UE) 2004 may also include a communications interface2085 that provides user access to the functions of the user equipment(UE) 2004. The user equipment (UE) 2004 illustrated in FIG. 20 is afunctional block diagram rather than a listing of specific components.

FIG. 21 illustrates various components that may be utilized in an eNB2102. The eNB 2102 may be utilized as the eNB 102 illustratedpreviously. The eNB 2102 may include components that are similar to thecomponents discussed above in relation to the user equipment (UE) 2004,including a processor 2187, memory 2181 that provides instructions 2182a and data 2183 a to the processor 2187, instructions 2182 b and data2183 b that may reside in or be loaded into the processor 2187, ahousing that contains a transmitter 2135 and a receiver 2133 (which maybe combined into a transceiver 2132), one or more antennas 2110 a-nelectrically coupled to the transceiver 2132, a bus system 2186, a DSP2184 for use in processing signals, a communications interface 2185 andso forth.

FIG. 22 is a block diagram illustrating one configuration of a UE 2218in which systems and methods for coordinated multipoint (CoMP) radioresource management (RRM) measurement may be implemented. The UE 2218includes transmit means 2247, receive means 2249 and control means 2245.The transmit means 2247, receive means 2249 and control means 2245 maybe configured to perform one or more of the functions described inconnection with FIG. 11 and FIG. 20 above. FIG. 20 above illustrates oneexample of a concrete apparatus structure of FIG. 22. Other variousstructures may be implemented to realize one or more of the functions ofFIG. 11 and FIG. 20. For example, a DSP may be realized by software.

FIG. 23 is a block diagram illustrating one configuration of an eNB 2302in which systems and methods for coordinated multipoint (CoMP) radioresource management (RRM) measurement may be implemented. The eNB 2302includes transmit means 2351, receive means 2353 and control means 2355.The transmit means 2351, receive means 2353 and control means 2355 maybe configured to perform one or more of the functions described inconnection with FIGS. 12 and 21 above. FIG. 21 above illustrates oneexample of a concrete apparatus structure of FIG. 23. Other variousstructures may be implemented to realize one or more of the functions ofFIGS. 11 and 21. For example, a DSP may be realized by software.

Unless otherwise noted, the use of ‘/’ above represents the phrase“and/or.”

The functions described herein may be implemented in hardware, software,firmware or any combination thereof. If implemented in software, thefunctions may be stored as one or more instructions on acomputer-readable medium. The term “computer-readable medium” refers toany available medium that can be accessed by a computer or a processor.The term “computer-readable medium,” as used herein, may denote acomputer- and/or processor-readable medium that is non-transitory andtangible. By way of example, and not limitation, a computer-readable orprocessor-readable medium may comprise RAM, ROM, EEPROM, CD-ROM or otheroptical disk storage, magnetic disk storage or other magnetic storagedevices, or any other medium that can be used to carry or store desiredprogram code in the form of instructions or data structures and that canbe accessed by a computer or processor. Disk and disc, as used herein,includes compact disc (CD), laser disc, optical disc, digital versatiledisc (DVD), floppy disk and Blu-ray® disc where disks usually reproducedata magnetically, while discs reproduce data optically with lasers.

Each of the methods disclosed herein comprises one or more steps oractions for achieving the described method. The method steps and/oractions may be interchanged with one another and/or combined into asingle step without departing from the scope of the claims. In otherwords, unless a specific order of steps or actions is required forproper operation of the method that is being described, the order and/oruse of specific steps and/or actions may be modified without departingfrom the scope of the claims.

As used herein, the term “determining” encompasses a wide variety ofactions and, therefore, “determining” can include calculating,computing, processing, deriving, investigating, looking up (e.g.,looking up in a table, a database or another data structure),ascertaining and the like. Also, “determining” can include receiving(e.g., receiving information), accessing (e.g., accessing data in amemory) and the like. Also, “determining” can include resolving,selecting, choosing, establishing and the like.

The phrase “based on” does not mean “based only on,” unless expresslyspecified otherwise. In other words, the phrase “based on” describesboth “based only on” and “based at least on.”

The term “processor” should be interpreted broadly to encompass ageneral purpose processor, a central processing unit (CPU), amicroprocessor, a digital signal processor (DSP), a controller, amicrocontroller, a state machine and so forth. Under some circumstances,a “processor” may refer to an application specific integrated circuit(ASIC), a programmable logic device (PLD), a field programmable gatearray (FPGA), etc. The term “processor” may refer to a combination ofprocessing devices, e.g., a combination of a DSP and a microprocessor, aplurality of microprocessors, one or more microprocessors in conjunctionwith a DSP core or any other such configuration.

The term “memory” should be interpreted broadly to encompass anyelectronic component capable of storing electronic information. The termmemory may refer to various types of processor-readable media such asrandom access memory (RAM), read-only memory (ROM), non-volatile randomaccess memory (NVRAM), programmable read-only memory (PROM), erasableprogrammable read-only memory (EPROM), electrically erasable PROM(EEPROM), flash memory, magnetic or optical data storage, registers,etc. Memory is said to be in electronic communication with a processorif the processor can read information from and/or write information tothe memory. Memory may be integral to a processor and still be said tobe in electronic communication with the processor.

The terms “instructions” and “code” should be interpreted broadly toinclude any type of computer-readable statement(s). For example, theterms “instructions” and “code” may refer to one or more programs,routines, sub-routines, functions, procedures, etc. “Instructions” and“code” may comprise a single computer-readable statement or manycomputer-readable statements.

Software or instructions may also be transmitted over a transmissionmedium. For example, if the software is transmitted from a website,server, or other remote source using a coaxial cable, fiber optic cable,twisted pair, digital subscriber line (DSL) or wireless technologiessuch as infrared, radio, and microwave, then the coaxial cable, fiberoptic cable, twisted pair, DSL, or wireless technologies such asinfrared, radio and microwave are included in the definition oftransmission medium.

It is to be understood that the claims are not limited to the preciseconfiguration and components illustrated above. Various modifications,changes and variations may be made in the arrangement, operation anddetails of the systems, methods, and apparatus described herein withoutdeparting from the scope of the claims.

What is claimed is:
 1. A method performed by a user equipment (UE),comprising: receiving a measurement configuration from an evolved Node B(eNB), wherein the measurement configuration comprises a measurementobject in a carrier frequency and the measurement object comprises a setof channel state information reference signal (CSI-RS) configurations;performing a measurement based on a cell-specific reference signal(CRS); performing a measurement based on a channel state informationreference signal (CSI-RS) based on the measurement configuration;generating a measurement report in a radio resource control (RRC) layer;and sending the measurement report to the eNB.
 2. The method of claim 1,wherein the measurement configuration comprises a measurement object,and wherein the measurement object comprises an information elementconfigured to perform at least one of adding a CSI-RS configuration tothe set of CSI-RS configurations, modifying a CSI-RS configuration ofthe set of CSI-RS configurations and removing a CSI-RS configurationfrom the set of CSI-RS configurations.
 3. The method of claim 1, whereinthe measurement configuration comprises multiple measurement objects. 4.A method performed by an evolved Node B (eNB), comprising: generating ameasurement configuration for a user equipment (UE), wherein themeasurement configuration comprises a measurement object in a carrierfrequency and the measurement object comprises a set of channel stateinformation reference signal (CSI-RS) configurations; sending themeasurement configuration to the UE; and receiving, from the UE, themeasurement report generated based on a measurement based on a channelstate information reference signal (CSI-RS) based on the measurementconfiguration.
 5. The method of claim 4, wherein the measurementconfiguration comprises a measurement object, and wherein themeasurement object comprises an information element configured toperform at least one of adding a CSI-RS configuration to the set ofCSI-RS configurations, modifying a CSI-RS configuration of the set ofCSI-RS configurations and removing a CSI-RS configuration from the setof CSI-RS configurations.
 6. The method of claim 4, wherein themeasurement configuration comprises multiple measurement objects.
 7. Auser equipment (UE) comprising: a processor; memory in electroniccommunication with the processor; instructions stored in the memory, theinstructions being executable to: receive a measurement configurationfrom an evolved Node B (eNB), wherein the measurement configurationcomprises a measurement object in a carrier frequency and themeasurement object comprises a set of channel state informationreference signal (CSI-RS) configurations; perform a measurement based ona cell-specific reference signal (CRS); perform a measurement based on achannel state information reference signal (CSI-RS) based on themeasurement configuration; generate a measurement report in a radioresource control (RRC) layer; and send the measurement report to theeNB.
 8. The UE of claim 7, wherein the measurement configurationcomprises a measurement object, and wherein the measurement objectcomprises an information element configured to perform at least one ofadding a CSI-RS configuration to the set of CSI-RS configurations,modifying a CSI-RS configuration of the set of CSI-RS configurations andremoving a CSI-RS configuration from the set of CSI-RS configurations.9. The UE of claim 7, wherein the measurement configuration comprisesmultiple measurement objects.
 10. An evolved NodeB (eNB) comprising: aprocessor; memory in electronic communication with the processor;instructions stored in the memory, the instructions being executable to:generate a measurement configuration for a user equipment (UE), whereinthe measurement configuration comprises a measurement object in acarrier frequency and the measurement object comprises a set of channelstate information reference signal (CSI-RS) configurations; send themeasurement configuration to the UE; and receive, from the UE, themeasurement report generated based on a measurement based on a channelstate information reference signal (CSI-RS) based on the measurementconfiguration.
 11. The eNB of claim 10, wherein the measurementconfiguration comprises a measurement object, and wherein themeasurement object comprises an information element configured toperform at least one of adding a CSI-RS configuration to the set ofCSI-RS configurations, modifying a CSI-RS configuration of the set ofCSI-RS configurations and removing a CSI-RS configuration from the setof CSI-RS configurations.
 12. The eNB of claim 10, wherein themeasurement configuration comprises multiple measurement objects.